Sumesh Chandra Upadhyay

Bio: Sumesh Chandra Upadhyay is an academic researcher from Central Salt and Marine Chemicals Research Institute. The author has contributed to research in topics: Bromide & Bromine. The author has an hindex of 5, co-authored 10 publications receiving 256 citations. Previous affiliations of Sumesh Chandra Upadhyay include Academy of Scientific and Innovative Research & Council of Scientific and Industrial Research.

Prospects for jatropha methyl ester (biodiesel) in India

Abstract: Jatropha Methyl Ester (JME) is a potential biodiesel in India. Although high quality EN 14214 grade biodiesel production from Jatropha curcas has been demonstrated by us for the first time, leading to a surge of interest worldwide, large‐scale cultivation of the plant with high seed productivity is critical to overall success. The core processes are carried out under ambient conditions and effluent discharge is eliminated through integration with by‐product recovery. A target of 2 tonnes (tonne = metric ton = 1000 kg) per hectare of jatropha seeds is realistic with proper agronomic practices in cultivable wastelands. Even so, only a small fraction of total diesel requirement can be met through biodiesel. Besides biodiesel, jatropha cultivation can make a considerable impact in promoting organic farming through use of the oil cake. The shell, having a calorific value equivalent to coal, can be made into briquettes and used in solid fuel fired boilers and other applications as a substitute for fossil fuel. ...

Four-fold concentration of sucrose in sugarcane juice through energy efficient forward osmosis using sea bittern as draw solution

Abstract: Clarified sugarcane juice (osmotic coefficient, φ, ∼1.01) was efficiently dewatered through the spontaneous process of Forward Osmosis (FO) employing sea bittern as draw solution. Sea bittern is the mother liquor that remains after recovery of common salt from seawater. It is either discarded to sea or evaporated to higher densities in solar salt pans for recovery of other marine chemicals such as bromine, Epsom salt, potash and magnesium chloride. Compared to seawater (φ = 0.905) which has limited potential as draw solution, the φ values of the sea bittern samples were in the range of 1.41 to 3.24, providing thereby a high osmotic drive. A polyamide thin film composite membrane was used in the study. With 1 bar applied pressure, room temperature operation, and 1 : 8 volume ratio of sugar cane juice to bittern (φ = 2.26; concentrations of main constituents (% w/v): Na+ = 2.83, K+ = 2.03, Mg2+ = 7.42, Cl− = 23.48, SO42− = 8.42), sucrose concentration in the juice was enhanced from 10.5% (w/v) to 40.6% (w/v) over 4 h, with average flux of 13 L m−2 h−1. Sucrose loss was <3%. Energy computations indicated a saving of 69 kg of bagasse per m3 of raw juice, assuming all process energy (steam/electricity) is derived from bagasse. Epsom salt of high purity was recovered from the spent draw solution upon chilling.

Sodium-sulphate production from sulphate-rich bittern: A parametric study and economic evaluation

Abstract: Concentrated brines and bitterns rejected from various processes contain mineral salts of economic value. For example, sulphate-rich bittern generated at saltworks in the Rajasthan state of India exceeds 3 million tons annually and requires adequate treatment. Resource recovery from such unutilized by-products presents a sustainable waste management approach. This work presents the development and evaluation of a process for sodium-sulphate (Na2SO4) recovery from sulphate-rich bitterns using an integrated process combining cooling crystallization, filtration, and drying as major unit operations. A parametric study has been conducted to investigate the effect of various operating parameters on product (anhydrous sodium-sulphate) yield and quality. Chemical analysis, TGA, P-XRD, and SEM-EDX techniques were used to characterize the product quality and purity. Based on the parametric studies, a sodium-sulphate production process was designed, and material & energy balance was established. The mass balance calculations have shown that 1 ton of anhydrous Na2SO4 (~97 wt% purity) can be produced from 6.31 tons of bittern having a sulphate ion concentration of about 140.8 ± 6.94 g/l. Subsequently, the economic feasibility of a 5 ton/day anhydrous Na2SO4 capacity plant has been evaluated using the cost and profitability analysis. The engineering-economic calculations suggest that the sodium-sulphate production from bittern can be economically favourable, achieving a payback period of 3.5 years. The optimized parameters and economics presented in this paper could significantly help implement an actual sodium-sulphate recovery unit using sulphate-rich bittern as feed.

Clean synthesis of crystalline p-nitrobenzyl bromide from p-nitrotoluene with zero organic discharge

Abstract: 2 : 1 : 3 NaBr-NaBrO3-NaCl (obtainable as a low cost and eco-friendly reagent from an alkaline bromine intermediate) has been utilized previously in a number of bromination reactions. One such reaction is the conversion of p-nitrotoluene (PNT) to p-nitrobenzyl bromide (PNBBr) used widely for functional group protection. In the present work, selective cold (0–5 °C) crystallization of PNBBr from the reaction mixture containing ca. 2.5 M PNBBr along with 2.5–5.0 M PNT in ethylene dichloride (EDC) was found to be a winning move which led to gains in two fronts. It allowed the bromination reaction to be carried out cleanly and also enabled direct recycling of the mother liquor in the subsequent batch. Para NO2-Ph-CHBr2 impurity, which built up gradually in the reaction mixture over 8 batches, was converted into PNBBr/PNT through treatment of the mother liquor with NaBH4, thereby helping to recycle the liquor perpetually and eliminate organic waste. EDC was the sole solvent in the entire process and its losses were minimal. The combined yield of isolated and recoverable PNBBr was 98.30% with respect to PNT consumed. The reagent utilization efficiency was 98.26%.

Biomass energy and the environmental impacts associated with its production and utilization

Abstract: Biomass is the first-ever fuel used by humankind and is also the fuel which was the mainstay of the global fuel economy till the middle of the 18th century. Then fossil fuels took over because fossil fuels were not only more abundant and denser in their energy content, but also generated less pollution when burnt, in comparison to biomass. In recent years there is a resurgence of interest in biomass energy because biomass is perceived as a carbon-neutral source of energy unlike net carbon-emitting fossil fuels of which copious use has led to global warming and ocean acidification. The paper takes stock of the various sources of biomass and the possible ways in which it can be utilized for generating energy. It then examines the environmental impacts, including impact vis a vis greenhouse gas emissions, of different biomass energy generation–utilization options.

Copper‐Catalyzed Aerobic Oxidation of Amines to Imines under Neat Conditions with Low Catalyst Loading

Abstract: The copper (I)-catalyzed direct synthesis of imines from amines under mild aerobic conditions is described. The method is applicable for the synthesis of various imines from corresponding amines such as benzylic, aliphatic, cyclic secondary, heteroaromatic species and the oxidative condensation of benzylamines with anilines extends the scope of the CuCl catalytic system. Noteworthy, solvent-free procedure, air as a benign oxidant, and the cheap and easy availability of the catalyst are the vital advantages of the method.

Utilization of methylarenes as versatile building blocks in organic synthesis.

Abstract: The development of practical and efficient methods for C–C and C–X bond formation has attracted a great deal of current attention with the advent of C–H functionalization reactions. Hydrocarbons are perhaps the most inexpensive and readily available materials, and utilisation of such materials for the synthesis of essential chemicals is virtually and economically pragmatic. The means to utilize easily accessible hydrocarbons not only represents a useful, potent and straightforward alternative, but also constitutes an excellent opportunity to improve our chemical knowledge about a relatively unexplored domain. Early examples using alkylarenes are generally limited to their conversion to aldehydes, carboxylic acids, and nitriles. This review intends to focus on the latest developments adopting modern strategies for sp3 C–H functionalization of methylarenes to achieve a diverse range of important organic compounds.